Lock-stitch sewing-machine.



P. W. MERRIOK.

LOCK STITCH SEWING MACHINE.

AYPLIOATION FILED JUNE 17. 1904.

906,730. Patented Dec. 15, 1908.

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Witnesses: Jhvenzforr v @Q/W T nc AjL J L vww PL 5 $1M M ZMW y 4 0; @a iF. W. MERRICK.

LOCK STITCH SEWING MACHINE.

APPLICATION FILED'JUNB 17, 1904.

906,730. Patented Dec. 15, 1908.

2 EJHBETS-SHEET 2 cation, reference being had therein to theaccompanying drawings.

unwinds therefrom, an

. the invention to a curved-needle look-stitch the machine, betweenthe-rim of the shuttle support for the thread in the turning move- -faceof the supply upon the bobbin to the Fig. g

FRANK W. MERRICK, 01 BOSTON, MASSAC USETTS.

LOCK-STITCH SEWING-MACHINE.

Specification of Letters Patent.

Patented Dec. 15,1908.

Application filed June 1'7, 1904. Serial No. 212,931.

T 0 all whom it may concern: I Be it known that I, FRANK W. MERRICK, acitizen-of the United States, residing at Boston, in the county ofSuffolk, State of Massachusetts, have invented a certain new and usefulImprovement in Lock-Stitch Sewin Machines, ofwhich the following isaspeci i- The invention consists in the combination, in a'waX-threadlock-stitch sewing machine, with a hook-needle operating to draw a 100of needle-thread through the stock which is being operated u on,'of arotary shuttle, and a central, or 'su istantially central, bobbin, thesaid bobbin rotatin only as the thread the shuttle-thread rendering fromthe said bobbin directly outward from the supply thereof which is woundupon the bobbin to the stitch-formingpoint in v and the marginal portionof the outer head or disk of the bobbin. The said rim is smooth anduninterrupted so as to afiord a'continuous ment of the shuttle, and thethread extends radially across the same directly from thesurstitch-iorrning point without being threaded through holes or thelike and without being bent from its direct course, being only deflectedby the shuttle rim.

The invention is equally applicable to machines of the straight needletype, and to ma chines of the curved needle type. I have illustratedboth of such applicationsin the accompanying drawings, in which latter,

Figure 1 shows in front elevation, with the work-support partly invertical section, a portion of a lock-stitch sewing machine. employing astraight hooked needle, with an einbodlment of the invention appliedthereto. Fig. 2 shows the parts of Fig. 1 in lan, with the,work-support, awlbar, and aw ornitted.

shows the devices of Fig. 1 in elevation, viewing the same from theleft-hand side in the latter figure. Fig. 4 is a detail view, mainly invertical section, on a plane passing transversely through the center ofthe shuttle at right angles to the line'of feed. Fig. 5 shows the shutte and bobbin in plan. Fig. 6 is a view illustrating the'application ofsewing machine.

Having reference, first, to the embodiment i of the invention in astraightmeedle ma chine, and to Figs.'1 to 5 of the drawings,- a portionof a post or standard forming part of the fran1e-work of astraight-needle sewing machine is represented at 1-, Figs. 1 and 2, andat 2 is-represented a work-rest or work,- support upon the upper end oithe said 0st or standard 1. 3 is an a'wlworking rom above the saidwork-rest or worlesu port, and 31 is an awl bar carrying thesai awl.Only aportion of the awl-bar is shown. 1 dis an ordinary hookedstraight-needle working from below the work-restor work-support, and 41isth'e needle-bar carrying the said needle, only a portion of theneedle-bar being shown". The awl-bar and needle-bar,:. in practice, resectivcly have connected-therewith suitab e means for reciprocating themove lengthwise in right lines. I. 5is arotwl'y shuttle. havingthe-workingkposition thereof below the work-rest or.work-sup-port, :theloo -taking point ofthe said shuttle being designated 59. The saidshuttle is essentially cu p-shaped, it being formed with alargebobbin-chainber which is surrounded by a raised annular rim, and beingrovided within the said chamber with a bob in-supporting post.

51. 52 is a bobbin which occupies the chan1- her and is mounted thereinu )on the said ost. 53, Figs. 1 and 2, is a s uttleadriver, and 54, Fig.1, is an upright shaft having the said shuttle-driver attached thereto,the said shaft being mounted. in hearings in the post or standard 1.. InJractice, the shaft 54- has connected therewith suitable means forrotating the same, not necessary to be shown.

6, 61, of the shuttle-race entering a ciroui'nferen'tial groove 55,which is formed inthe exterior of the shuttle, and the removability ofthe section 61 )roviding for the insertion and withdrawal 0 the shuttle.

As thus far described, the parts are not of the 'st of the invention.'lhey may be of the. illustrated construction, etc., or other- I *wise';as deemed desirable in ractice. They are caused to operate as usua inhook-needle wax-thread -sewing 'inachi-n'esi Thus,.1the

awl asses through the st'ockfrom'one' sideiof 'theatterto form a holetherein. The needleis passed through the said holefrom the opposite-sideof the stock, and after having had the needle-thread placed its open eyeby the action of the thread-guide (looper) is retracted, drawin a 100"of needle-thread through the said be e. T e said loop is en gaged bythe shuttle-point and by the rotation of the shuttle is completelydisengaged from the needle, after which it is passed around and over theshuttle, whereby it is interlocked with the shuttle-thread, being thendischarged from the shuttle-point and drawn up to tighten and completethe stitch. 4 Having reference, now, to the features in which myinvention more immediately resides,As shown in the drawings, the

bobbin-chamber of the shuttle is concentric the shuttle and bobbin aredispensed with,

and the shuttle-thread is' conducted from the exterior of the supply,thereof which is wound u on the bob in outwardbetween the rim 0 theshuttle and the marginal por-,

. tion of the upper, (i. -e., outer) head or disk the shuttle, the

of the bobbin, to the stitch-forming point in the machine. During therotation of ortion of shuttle-thread which leads from tlie bobbin to thesaid point retains substantiallythe same position in space, the rimof'the shuttle turning with relation thereto, and the bobbin turning onits axis only as the thread unwinds therefrom. In virtue of the centralposition of the bobbin with reference to the axis of rotation of theshuttle, the bobbin remains uniformly distant from the stitch-formingpoint in the machine during a rotation of the shuttle. In consequence ofthe foregoing facts, the tension of the portion of thread, 0,, Figs. 1and 4, that extends from the bobbin to the said point is not variedduring such rotation, as it is in instances in which the bobbin ismounted eccentrically in the shuttle, and in those in which the threadin issuing from the shuttle leaves the latter by a guide locatedeccentricaliy with reference ts the axis of rotation and operating'tocause the thread to travel in r a circular path around the said axis asthe shuttle rotates. The delivery of the shuttlethread from theperiphery of the central bobbin, directly outward over the edge of therim around a center with reference rte "which it is mountedeccentricallyfas well as in after leaving the bobbin a turn or twist isim 'arted to the shuttlethread or taken" out of the same for eachrotation of the shut-" tle.' In addition, in the case of a centrallylocated cop, from the interior of which the thread is drawn, there isone turn of twist put into or taken out of the shuttle-thread for eachcoil which is unwound from the said cop.

At 9, Figs. 1, 3 and 4,'is a spring which may be employed, if desired,to hold the bobbin from rising in the shuttle. It is a leaf-spring,attached by one end thereof to the underside of the worksupport, havinga depressed intermediate portion to 7 act in connection with the uppersurface of the outer (up er) head ofthe bobbin.

At 91, lfiig. 4 is an adjusting screw by means of which the position ofthe movableportion of the spring may be adjusted vertically.

The invention is equally applicable either to straight-needle machines,as already described, or to curved needle machines, asin Fig. 6. In thelatter figure, a work-support is indicated 111, a curved awl at 112, an

oscillating awl-carrier at 121, a curved needle at 113, and anoscillating needle-carrier at 131. "ihese parts are or may beconstructed and operated as usual in curved, hook-needle sewingmachines. At is a rotary shuttle coiiperating with the said curvedneedle in the production of stitches, 159 being the shuttle-point, 152the shuttle-driver, 154 the rotary shaft on which the saidshuttle-driver is mounted, and 156 the shuttle-race. In

ice,

all essential respects, as regards the inven 3:1

tion, the shuttle and bobbin oi the curved. needle machine are as air-e'13? described and as shown. in the preceding figures. An tic oryielding arm 119 is attached by mea of the screw to the portion 12 of timachine-framing. The free extremity oi said arm projects in advance ofthe sin and makes contact with the-outer side of disk 118, which may beone of the heads the bobbinl The said arm serves ,to rete the said dishand bobbin in place within shuttle. l

' I claim as my invention In a wazethread, loch-stitch sewing chine, incombination, a hooh needle operas ing to pass a loop of needle-threadthrough the stock which is being operated upon, a rotary shuttle bywhich the said loop is completely disen a ed from the needle and passedaroun t e shuttle, the said shuttle eing formed with concentric openbobbinchamber and with a smooth uninterrupted rim around the o ening ofsuch chamber which rim as it revo ves with the shuttle constitutes acontinuous unbroken support over which the bobbin-thread may draw, andan uncased central bobbin within the said chamher from which theunwinding thread passes radially across said rim to the stitch-formingpoint, the said thread rendering directly outward to and over the saidrim from the periphery of the supply thereof which is wound upon thebobbin.

In testimony whereof I aflix my signature in presence of two witnesses.FRANK W. MERRICK.

\Vitnesses:

CHAS. F. RANDALL, EDITH J. ANDERSON.

